Opportunities and Challenges for Commercialization of Fuel Cells

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1 Opportunities and Challenges for Commercialization of Fuel Cells Ajay K. Prasad Professor, Department of Mechanical Engineering Director, Center for Fuel Cell Research Director, UD Fuel Cell Bus Program University of Delaware 2014 UDEI Annual Symposium May 14, 2014

2 Growing Interest in Fuel Cells Antarctic ice sheet collapse underway- Washington Post Atmospheric CO2 A large sector of the West Antarctic ice sheet has gone into irreversible retreat. It has passed the point of no return. Eric Rignot, UC Irvine in the New York Times.

3 Where do CO2 emissions come from? 70% of petroleum in the US is used for transportation (diesel, gasoline, jet fuel) There are approximately one billion vehicles worldwide in operation today

4 What is a Fuel Cell? Hydrogen Fuel Cell Oxygen Heat Electric power Water A fuel cell combines fuel and oxidant electrochemically to produce electricity Two to three times more efficient that an internal combustion engine Fuel cell stack is quiet, has no moving parts, produces zero emissions

5 H 2 Load e - Air Anode H + Cathode NIST Bipolar plate Gas Diffusion Layer Anode Reaction 2H 2 4H + + 4e - Membrane Electrode Assembly Gas Diffusion Layer Bipolar plate Cell voltage = 0.6V Cathode Reaction O 2 + 4H + + 4e - 2H 2 O

6 NREL Fuel cell stack

7 Honda FCX Clarity Launched in 2008; World Green Car 2009 About 25 FCXs being leased in CA; $600/month (incl. maintenance and insurance) Launch of Honda s next-gen FCEV Concept in 2015 with 33% smaller fuel cell stack

8 GM s Chevrolet Equinox FCV 119-vehicle Project Driveway Program in CA (2007) More than 5,000 drivers 3 million hydrogen-powered miles

9 Millions of vehicles Toyota to launch hydrogen-powered car in 2015 Initial launch in CA (SF Bay Area, LA, Orange County, San Diego) Toyota FCV 68 filling stations to handle 10,000 FCVs Toyota Hybrid Sales (cum.) $200 million from CA for 20 new stations by 2015, 40 by 2016, and 100 by Prius launched FCV to be launched

10 Hyundai Tucson FCV can be leased starting 2015 Tucson FCV $499/month (Including fuel and maintenance) $2,999 due at lease signing 36-month lease Up to 1,000 Tucsons/year depending on sales Limited to CA

11 Mercedes-Benz could launch next fuel cell car in 2017

12 Recent announcements by automotive companies GM, Honda to collaborate on next-gen fuel cell technologies Goal is commercially feasible fuel cell and hydrogen storage in 2020 time frame GM and Honda rank #1 and #2 in total fuel cell patents filed between 2002 and 2012 More than 1,200 patents between them Ford, Nissan, Daimler to jointly develop a mass-market hydrogen fuel-cell car by 2017 Maximize economies of scale by sharing investment costs Resulting fuel cell will be used to launch highly differentiated, separately branded FCEVs BMW, Toyota to jointly develop fuel cell system for production cars (fuel cell stack, hydrogen tank, electric motor, and battery)

13 Fuel cell patents granted Fuel Cell Solar Wind US patents US & Euro. patents Patents granted 2012 Fuel Cell Patent Review, Fuel Cell Today

14 Current fuel cell car prototypes Vehicle Year Shown Fuel Cell Size/Type Range (km) Fuel Type Audi Q5 HFC kw PEM N/A CH 2 (700 bar) Daimler EcoVoyager kw PEM 483 CH 2 (700 bar) Daimler Mercedes-Benz B-Class F-Cell kw PEM 385 CH 2 (700 bar) Fiat Panda kw PEM 200 CH 2 GM Provoq kw PEM 483 CH 2 (700 bar) GM HydroGen4/Equinox kw PEM 320 CH 2 (700 bar) Honda FC Clarity kw PEM 386 CH 2 (350 bar) Hyundai Tucson ix kw PEM 650 CH 2 (700 bar) Intelligent Energy Black Cab kw PEM 400 CH 2 (350 bar) Kia Borrego/Mojave kw PEM 685 CH 2 (700 bar) Kia Sportage II kw PEM 328 CH 2 (350 bar) Morgan LIFEcar kw PEM 402 N/A Nissan X-Trail FCEV kw PEM N/A CH 2 (700 bar) Suzuki SX4-FCV kw PEM 250 CH 2 Toyota FCV-R 2011 N/A 700 CH 2 (700 bar) Toyota FCHV-adv kw PEM 830 CH 2 (700 bar) VW Passat Lingyu kw PEM 300 N/A VW Tiguan HyMotion kw HTFC 200 CH 2 (700 bar) Only vehicles introduced since 2007 are included.

15 Fuel cells for materials handling Compared to conventional forklifts, fuelcell-powered forklifts: Produce no local emissions Can operate in stringent food industry applications Quick refueling compared to batterypowered forklifts Can work in refrigerated warehouses unlike Li-ion battery powered forklifts Over 4,000 fuel cell forklifts in operation in 2013 in the US (SYSCO, Coca-Cola, Wegmans, Whole Foods, FedEx, etc.) Annual forklift sales ~1 million ($30 billion) Plug Power to supply Walmart with 1,738 GenDrive fuel cell forklifts

16 Pros and Cons of Fuel Cells Advantages of Fuel Cells Challenges Facing Fuel Cells 1. Higher efficiency compared to IC engines 2. Zero emissions at the point-of-use 3. No moving parts in the stack, so quieter 1. Cost (materials, labor, economy of scale) 2. Durability (membrane, catalyst) 3. Lack of H2 Infrastructure: H2 is difficult to produce, transport, and store

17 Center for Fuel Cell Research System-level Materials Operational experience Hydrogen storage 1. PEM fuel cells 2. DMFC 3. SOFC 4. Hydroxide exchange membrane fuel cells Batteries Solar Hydrogen Generation

18 Research with Single-cell Devices H 2 O 2 Bipolar Plate Gas Diffusion Layer Electrodes Gas Diffusion Layer Bipolar Plate NIST Materials: membranes, catalysts, GDL, cell architecture Operating protocols and strategies: cell temperature, reactant stream flow rates, temperatures, and humidities Performance and durability testing Accelerated stress testing: wet/dry cycling; freeze/thaw cycling; characterize degradation and failure modes

19 1. Freeze/Thaw Cycling of Nafion/MWCNT Membrane Temperature One Cycle 70 C 40 min 25 C -20 C 90 min Time Nafion 112 MWCNT/Nafion Hydrogen Crossover Nafion 112 MWCNT/Nafion Delamination at membrane/electrode interface Wang et al., J Electrochemical Society, 2011 Reinforced membrane has better tensile strength and durability Better dimensional stability delays delamination during freeze/thaw cycling.

20 Voltage, V Eletrical Resistance 2. Composite Membrane Based On SiO 2 /MWCNTs 4.4x10 6 ohms CNTs can increase electronic conductivity in the through-plane direction. 4x10 7 SiO 2 coating on CNT can insulate CNTs so higher loadings of CNTs can be applied. 3x10 7 2x x10 6 ohms Also, SiO 2 absorbs water which can be released under dry conditions. 1x x10 6 ohms SiO 2 /MWCNTs 0 2% MWCNTs/Nafion 4% SiO2-MWCNTs/Nafion Recast Nafion Electrical resistance Membranes of membranes NR % RH NR % RH SiO 2 /MWCNTs/Nafion 40um 100% RH SiO 2 /MWCNTs/Nafion 40um 50% RH 2% MWCNTs/Nafion 47um 100% RH 2% MWCNTs/Nafion 47um 50% RH TEM of SiO 2 /MWCNTs SiO 2 -MWCNTs/Nafion membrane Wang et al., J Electrochemical Society, Current Density, ma/cm 2

21 3. Variable-area Ejector for Hydrogen Recirculation Patent pending Employs a stepper motor-leadscrew based linear actuator for ease of control. Simple PI pressure feedback control system on a custom-designed circuit board. Working well on both UD fuel cell buses. Brunner et al, Int J Hydrogen Energy, 2012

22 Mass of H2 stored per unit volume of tank (g/cm3) Mass of H2 stored per unit volume of tank (g/cm3) 4. H2 storage systems employing solid-state materials Hydrogen inlet T f, h f Contours of H2 storage z T f, h f 0% Al foam 10% Al foam, h Wang, Prasad, Advani, Int J Hydrogen Energy, 2012 r T f f 3 min charge Internal cooling tube Effect of pitch Effect of heat transfer coefficient (a) (b) no aluminum foam is added 5% aluminum foam 10% aluminum foam h=250 W/m 2 -K h=500 W/m 2 -K h=1000 W/m 2 -K h=2500 W/m 2 -K h=5000 W/m 2 -K no aluminum foam is added Non-dimensional pitch = Filling time = 6 min Non-dimensional pitch Convection heat transfer coefficient h (W/m 2 -K) Wang et al., Int J Hydrogen Energy, 2012

23 5. Solar Hydrogen from Thermochemical Cycles Concentrated sunlight (2000 K) O 2 vent ZnO Zn + ½ O 2 Metal oxide decomposition ZnO Zn H 2 product Zn + H 2 O ZnO + H 2 Water splitting Steam Net inputs: sunlight, water Net outputs: H 2, O 2

24 Gravity-Fed Solar-Thermochemical Receiver/Reactor (GRAFSTRR) 1 1. Water-Cooled Quartz Window 2. Water-Cooled Aperture 3. Data Acquisition Ports 4. Pure Alumina Reaction Tiles 5. Solids Outlet 6. High Temperature Insulation 7. Gas Outlet

25 A B C Solar simulator at PSI, Zurich Bottling sunlight

26 Success! Simulated temperature for 15 kw solar flux input The future? Power-Tower and Heliostat Field Measured reactor temperatures at 3.5 kw Koepf et al., Int J Hydrogen Energy, 2012

27 Summary Fuel cell market appears poised for take off. Issues surrounding cost, durability, and infrastructure will continue to challenge widespread commercialization. UD Center for Fuel Cell Research is engaged in all activities relevant to fuel cell commercialization.